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The ????? ???? ???? ????????Arctic, beset by unusually warm temperatures this summer, is ripe for flames.

Parched forests and dense vegetation across the expansive region have been ignited relatively easily by lightning strikes. Hundreds of wildfires are now burning in Siberia, wafting dense smoke over the high northern region.

"The unusual thing about this year has been the number and distribution of fires north of the Arctic Circle in Siberia, Alaska, and more recently in Canada," said Mark Parrington, a senior scientist at the European Union's Copernicus Atmosphere Monitoring Service. "Conditions were certainly warmer and drier in June and that may also be the case for July when the data are available."

The World Meteorological Organization recently called the Arctic wildfires "unprecedented." In June alone, the wildfires released more carbon into the atmosphere than Sweden does in an entire year.

And the fires have persisted.

For nearly 50 straight days, wildfire activity in the Arctic Circle was well above average. As a result, carbon emissions from the region this July were dramatically higher than usual.

Atmospheric scientists, like Parrington, use satellite observations from NASA satellites to measure how much radiation the fires are releasing. Then, accounting for the type of vegetation burning (like carbon-rich peatlands), they can estimate the heat-trapping carbon emissions.

Forests are often considered a place where carbon is sucked out of the air and sequestered in the soil and vegetation (known as "carbon sinks"). But the Arctic is proving to be an unusually potent source of carbon this summer, adding to the planet's already skyrocketing atmospheric carbon levels.

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Alaska, too, has experienced above normal burning this summer, which has swamped large swathes of the state in smoke. This is little surprise: July 2019 will almost certainly go down as the warmest month ever recorded in Alaska, noted climate scientist Brian Brettschneider.

Meanwhile, sea ice in the whole of the Arctic remains dismal this summer. The ice -- melted by both a warmer atmosphere and ocean -- is presently at record lows for this time of year.

The rapidly warming Arctic may very well be free of summer sea ice later on this century. A smokier, increasingly fire-prone Arctic is a likely future, too.

"It is difficult to say with certainty but with warmer and drier environmental conditions the likelihood of fires occurring increases," noted Parrington.